Sunday 3 November 2013

TV and Telephone Voting

Television shows that take place over the course of an evening which are decided by telephone voting are frequently blighted by what I call the "I've just come in from the pub mob" and the "I've watched something else and then just flipped over for the end posse".

The problem
What happens is these groups of people both only see the end of the show and then, understandably, vote for one of the later candidates/acts/talents (CATs), because that's one of the ones they've seen. This gives the final CAT a significant advantage over everyone else and, indeed, depending on the country's pub culture and the other programmes on that evening with significant viewing shares, each CAT an advantage over all the ones who were on before them.

Solutions so far
There are measures designed to counteract this. One is having each CAT having to do something more than once. If, in a singing show with three CATs, each CAT has to sing twice, then you at least have CAT1 singing once after each of CAT3 and CAT2 has sung their first song (assuming a 1,2,3,1,2,3 order) - or you could have a different order like 1,2,3,3,2,1 to try to maximise fairness. Whatever you do though, you have one CAT who's on last and who catches the votes of the aforementioned mob and posse.

Another idea is to open the voting lines straight away, before any CATs have even been on stage. This is flawed insofar as it means that people who vote based on a performance have more time to vote for certain CATs whilst people who just vote based on prior sympathies can vote regardless of what the CATs actually do on the night.

So if we want a fair vote reflective of people's assessments of what the CATs have done during the show, this doesn't work. You could argue that being able to vote for CAT1 balances out the swing to CAT3 from the mob and posse, but having two terrible features in a system and hoping they approximately balance one another out is a bit like throwing a few nukes around and hoping more baddies than goodies die: neither scientific nor likely to work.

What you could do
My suggestion is to get people to register to vote. This would take place in the waffle that happens at the start of the show before any CATs have been on. This segment usually takes at least 15 minutes (on a standard Saturday evening format) and is ample time for people who are generally interesting in digging in for the evening to send a short text message (SMS) or ring up a number.

By registering they would make themselves (or anyone with the same phone number) eligible to vote during the voting phase, which would only begin after the last CAT's last performance. This seems technically straightforward to implement and would restrict voting to those people who have seen the whole show and so can make a fair decision. Clearly, some people might have some chips or something and miss one of the CATs, but you can imagine people's chip-eating habits to be varied enough for this to even itself out and not significantly (dis)advantage one CAT over another.

I don't really see many problems with this. You could, for example, easily adjust the price of calls to stop having to ring in twice hitting the voters' bank balances too much. It doesn't solve the fact that some certain audience sections (with some correlation with the kind of CAT they like) are more likely to take part in a phone vote than others, but that's true of all votes. At a parliamentary election, there are some sections of the electorate who would rather go down the pub than go cast their vote. And they automatically get underrepresented in the House of Commons.

The only real flaw I can see in this system is that it would probably lead to fewer votes coming in, which would mean less money being made. But if there has to be a victim for the sake of overall fairness, then you could find a worse one than television producers.

Sunday 20 October 2013

FIFA rankings and football's interestingness

This week, the group stages of UEFA qualifying for the 2014 football World Cup came to an end. The draws for these groups were based on the FIFA world football rankings we know and love.

I read an article by Gabriele Marcotti, who sometimes writes reasonable things, written before the final round of qualifying matches. I've done a semi-close read of it here, followed by some of my own stuff. I'm focusing on the bit of the article that deals with the UEFA section of World Cup qualifying.

Here we go - Marcotti quotes in italics
"UEFA get 13 spots in the World Cup. Nine qualify directly and another four via two-legged playoff."

Fair enough.

"And of the 13 highest-ranked nations who went into qualifying, just two -- Denmark (eighth at the time) and the Czech Republic (13th) -- are out of the running."


Seems to make sense.

"Three of the top six -- Germany (second), Italy (fifth) and Holland (sixth) -- have already clinched a place. Another two -- Spain (first) and England (third) -- should also win their groups and guarantee passage."

This was written before the final round - Spain and England did indeed win their groups.

"The one team that have significantly underperformed are Portugal -- fourth at the time but who have had a tricky qualifying campaign -- though they are heavily favored [sic] to make the playoffs."


"Fourth at the time but have had a tricky qualifying campaign" doesn't seem to mean anything. Surely fourth because they've had a tricky qualifying campaign.

"Greece (10th at the time), Russia (ninth), Sweden (12th) and France (11th) have already made at least the playoffs, while, in addition to Portugal, Croatia (seventh) are also just about there."


This is where it really starts going downhill, as it exposes some clumsiness. Marcotti is clearly working with the rankings published in August 2011, rather than on 5th September 2011 (first qualifiers took place on 7th September).

"Some will point to Switzerland (14th) and Belgium (29th) and the fact that they've clinched qualifying as evidence of surprises. But really, Switzerland’s track record (and a fairly cream-puff group) and Belgium's deep and talented squad suggest that many saw this coming."


These might be points worth making but they have nothing to do with the rankings, but shoving them into a piece which you’re trying to write to say “the rankings work” (more on that later) doesn’t strike me as being overly scientific.

"Bosnia (19th) is a great tale given the nation's history." Actually 17th if you use the right rankings.

"They're guaranteed the playoffs and could yet win the group, but again, looking at the talent in the squad and the relative weakness of the group, it's not really a shock."


"It's not really a shock" is again something which makes any look at the rankings irrelevant if you can just claim that any time they don’t work then you might as well not look at them at all. It's a bit like selective reading of the bible (which I'm not suggesting Marcotti does).

"Iceland -- 46th in Europe, 130th in the world when qualifying kicked off –" actually 44th and 118th. "have a shot at the playoffs, which would be remarkable for a nation of just 300,000."

Seems to be a fair point – the least populous nations getting to playoffs in recent World Cup or Euro qualifiers would be Montenegro and Estonia, both of whom have populations well above 300,000.

"But given the seeded playoffs and the possibility of facing France or Portugal, the shock would be if their journey did not end there."


The seeded playoffs mean that Iceland can’t face France. And suggesting that the seeded playoffs mean it would be a shock if Iceland didn’t win gives an awful lot of credence to the ranking system which, elsewhere, can be dismissed simply by taking a look at talent in a squad. Or, on the other hand, you're assuming the effectiveness of the ranking system within your argement for its effectiveness.

"What all [Marcotti's all includes similar analyses of the other continental federations] this suggests is that maybe the FIFA rankings aren't as absurd as they sometimes seem. Or, at least, they weren't this time around. The vast majority of the teams that were supposed to make it did make it."

Clearly, Marcotti is confusing the rankings, which are supposed to recognise previous achievement, with some kind of tool for predicting future achievement.


I don’t think the word “supposed” is appropriate in this case, because he’s taken the rankings at a time which is irrelevant for the organisation of the competition, August 2012. (That he meant to take September 2012 doesn't matter in this instance.)

The only time when the rankings actually influence who teams face is at the draw, when the teams are sorted into pots – this is a deliberate attempt to improve the best-ranked teams’ chance of qualification by keeping them apart. If there is any “supposed to” anywhere, then it is here.

Of the nine teams that went into pot 1, five have qualified. This is about 55.56 % - a simple majority but not a vast one.

Of the nine teams that went into pot 2, one has qualified and two have made the playoffs, that’s 33% (a minority) doing anything remotely reasonable.

What if we try to be a bit more scientific?
As a little experiment, I did the following:

Gave all teams a score according to the pot they were in at the draw (pot 1 is 1 point, pot 2 is 2 points and so on).

Looked at the possible total points for all group winners and playoff reachers. Here, I doubled the points for a group win as a mechanism for weighting this more than reaching the playoffs. I think this works.

So the lowest possible total is ((9*1)*2)+(8*2) = 34

The highest possible total is ((8*6)+5)*2+(8*5) = 146

The lowest total would be if all pot 1 teams won their group and all playoff reachers came from pot 2. The highest would be if all pot 6 teams won their groups and all playoff reachers (and the group winner from the 5-team group) came from pot 5.

This gives us a possible range of 146 – 34 = 112 points.

The score of the actual group winners and playoff reachers comes out as 52.

This is 18 above the lowerst possible, in a range of 112, putting it at the:

18/112 = 16.07th percentile.

This gives us something I feel can be a useful figure for measuring how closely the rankings have “predicted” the results of qualification. I’m not suggesting any “supposed to” here, but a higher percentile would indicate that lower-ranked teams did better than the rankings would have “predicted”.

It’s up to the observer whether he wants to question the ranking system or applaud the interestingness of international football for not always having teams perform exactly as well as they have done over the past four year period used for ranking-point calculation.

If we get a bit more detailed and use the UEFA ranking of each team, rather than just a pot (so Spain are 1, Netherlands are 2 and so on), then the result comes out around the 13.49th percentile. And if you take the FIFA ranking, you get the 9.79th percentile.


This would seem to suggest that the more detailed you get (i.e. the more you reflect the relative strengths of the teams in the points you assign them), the better the rankings are at predicting the results and the less interesting the qualifiers become.

It’s only a one-off though, so all we can see at this stage is that in this case the better-ranked teams in each pot did better than the worse-ranked teams from the same pot. Generally speaking.

Anyway, having a nice figure like this also means that we can look, for example, at what the figure is if we take the rankings just before the qualifiers (not Marcotti’s August ones, the September ones).

If we do this and go through all the same calculations (being a little careful because, for example, there isn’t a team in the top 9 (pot 1) in every group), then we get the actual results as being at the 10.48th percentile. This is a marked improvement over the 16.07th percentile we had when we took the rankings at the draw.

Similarly, the percentiles when using the UEFA and FIFA rankings also both improve, from 13.49 to 8.84 and from 9.79 to a very respectable 6.57.

So the main issue this highlights is the fact that the draw is made based on rankings over a year before play begins, by which time the rankings have changed considerably. And, as you would probably expect, the rankings immediately before the games start are a better indicator than those at the time of the draw.


Sweeping statement check
It also lets us look sensibly at some things Marcotti said. He refers to Switzerland’s group as “fairly cream-puff”. Whilst the group as a whole is, by total ranking (at time of first game) of all teams, 6th out of 9 and slightly worse than average, Switzerland were the highest ranked side in it, despite being in pot 3.

This is, for my money, far more relevant than overall group strength because it explains why Switzerland were the ones to emerge from the (slightly) weak group.

Bosnia’s group is also said to display “relative weakness”. According to ranking, it is indeed 8th of 9, but, more importantly, Bosnia are the second best-ranked team in it, so have only actually overcome Greece (difference of 8 ranking points) to win the group.

And Belgium, far from simply having to rely on a “deep and talented squad”, were also 2nd best in their group and have only had to overcome Croatia (albeit making up 15 ranking places).

And if we go back to Iceland, regardless of their population, they have overhauled three better-ranked teams with a combined superiority of 64 ranking points. Next best, but a long way back are Romania, who also overhauled three teams, but only made up 27 ranking points in the process.

Hope you enjoyed all that.

[These italics aren't from Marcotti.] PS: If you're trying to recreate my calculations, it's possible you'll get minimally different results, as there are different ways of treating countries of level ranking. Don't worry about it.

Thursday 19 September 2013

Equilibrium in the Champions League III

This is just a very short post as a follow up to the two previous posts in this trilogy, which can be found here and here. Basically, those posts looked at how you could get complete equilibrium in the Champions League group stages, based on the teams' UEFA club rankings and then based on their coefficients.

This post is basically just a correction. I hadn't realised that Real Sociedad, although they had not been in European competition in the five years used as the basis for coefficient calculation, nevertheless have their coefficient calculated for the purposes of the draw. Whilst they don't get any points for their own achievements, they do get the 20% of Spain's national coefficient, which isn't too shabby at all and is actually enough to put them in 31st, above Vienna.

This therefore messes up the calculations I made in those posts for balanced groups and you can't even just make a simple swap of Real Sociedad and Vienna because I had Vienna in Barca's group. The word fiddlesticks comes to mind.

Another point is that, as Sociedad also don't have 0 coefficient points, but 17.605, the calculations for balanced groups would also be different. And it means that they wouldn't be 451st in Europe overall, but would be somewhere around 87th, meaning that balanced groups based on the overall UEFA club rankings are much more possible than I made out.

Whilst this is all quite disappointing, as it voids my results, it doesn't, I don't think, void the methodology, which I am convinced will stand the test of time.

Whilst I'm not going to redo all of the calculations, I can tell you that Sociedad's being ranked 31st of the Champions League qualifiers means that Man United aren't actually as lucky (l) as I'd made them out to be, as they get a luck score of just 1.33 and not 1.67. This doesn't however, affect the bigger picture of English luck, as they remain the only English side with positive (i.e. good) luck, based on the UEFA rankings.

Sorry about the error.

Wednesday 18 September 2013

People who write alright are all right

Now it's possible I've written a post on this before. I don't think I have though so I'm writing it now, albeit with the small chance of my repeating myself.

I'll be brief. Already doesn't mean all ready. Always doesn't mean all ways. Alone doesn't mean all one. In each case, the first word has developed from a combination of the other two words to ultimately express a new thought or idea. This is a highly useful feature of language development.

Alright doesn't mean all right.
If I say "they're all right", then I am only talking sense if the "they" in this instance have just all said something like "two times two is four". In that case, they are all right. If one of them says "two times two is twenty-two" then they're no longer all right, as one of them is wrong.

If I say "they're alright" then it is possible that they have all said "two times two is four" but this is an irrelevance. Of far more importance is whether the bus that has just threatened to flatten them has done so or not. If it hasn't, then "they're alright" is a sensible comment. If it has, even if it's only flattened some of them, then "they're alright" is ill-judged, regardless of whether or not they've just said that two times two is four or twenty-two.

This is pretty obvious, but nevertheless worth saying. I don't have any dictionaries to hand so I can't tell you if they all agree with me or, in other words, if they're all right or not. In any case, I'm not here to bag on dictionaries. Most are not perfect because they contain many errors resulting from the fact that they are constantly playing catch-up. But they're generally alright.

Sunday 15 September 2013

The best thing

Hello,
This is just a short post, making use of Google's Ngram Viewer which we all know and love. In case anyone doesn't know about Ngram, it lets you search for word or phrase usage in books over time and gives you a nice graph. So you can see when certain words or phrases were most popular and things like that.

Anyway, inspired by this phone-in on Alan Partridge's Mid-Morning Matters, where the presenter invites listeners to suggest the "best thing ever" and someone says "sliced bread", I decided to have a do a little bit of research.

According to Wikipedia, sliced bread was first sold in 1928 and yet, according to Ngram, the phrase "best thing since sliced bread" only really started appearing in literature around 1974. However, some slightly less half-hearted research shows that "greatest thing since sliced bread" emerged in 1950 and really gained pace around 1962. If we just use "thing since sliced bread", then the first record is in 1947, three years after the famous pre-sliced bread ban of '43, with a real increase in usage in the 1960s, after which it goes up fairly steadily up to the present day.

It's hard to make cast-iron deductions from this information, but the following are possible:
  • early sliced bread, invented in the 20s, wasn't all that great and only really won over American hearts when it improved dramatically in the 1960s
  • sliced bread was immediately excellent in 1928 but it takes time (around 30-40 years) for phrases like this to develop and find their way into written literature
  • sliced bread was good ever since 1928 but there was something else which was still considered better, the popularity of which declined in the 1960s, opening the way for sliced bread to take its place in the phrase
If we consider that the last of these possibilities is indeed possible, then it might be interesting to know what the idiomatic "best thing" (or "greatest thing" etc.) was before sliced bread. If we run "best thing since" through Ngram, we see it first emerge in 1855, with fairly undular, but not insignificant, activity up to the mid 60s, where a real rise can be observed, similar in trajectory to that of the "thing since sliced bread".

Clearly, all "best thing since" happening before 1928 cannot possibly be referring to sliced bread (unless appearing in some obscure and remarkably prescient sci-fi publications) and, if we believe Ngram, most things before the 1960s and all things before 1947 must have referred to other things too. So what might these have been?

Now the scope of the Massive Blog doesn't allow for a very thorough investigation, but a quick and haphazard click through the links underneath the Ngram give us the following candidates for "best thing" from the period 1800-1914:
  • John Bourne, writing in 1878, "I put this heavy mineral oil as the best thing since compound engines."
  • William Mumford Baker, writing in 1883, "It 's the best thing since the war broke out."
  • The World's Work, in 1903, stating that "As a political novel ... "The Henchman," by Mark Lee Luther, is the best thing since "J. Devlin Boss"".
The other examples of "best thing since" from this period are red herrings, because they include punctuation and use "since" to mean "because". For example, American Poultry Advocate wrote in 1905: "We heard it suggested that it should have a separate building, but this seems to us hardly the best thing, since it would, in a measure, set it off by itself; we would much prefer that this exhibit be a part of the regular poultry exhibit". So these can be discounted.

Also, the second listed example, "best thing since the war broke out" is probably to be treated with caution, as it a) only really works when the war is still going on and b) isn't necessarily putting the outbreak of war as something good to be compared to, but rather suggesting that all has been rotten since this time. Indeed, the third example is also only valid in the context of political novels and so also not really equivalent to the usage of "best thing since sliced bread". So we're left with compound engines as the idiomatic best thing of the 19th Century.

To finish off, because I don't want the post getting too long and you're free to continue the research yourselves, I'll look at the period before "best thing since sliced bread" caught on. Here is one of the more interesting examples:
  • The best thing since ice cream is also the best thing since canned pudding.(Life Magazine, 1971)
This seems to be an advert for Birds Eye's Cool and Creamy Cups, which also contains the slightly nonsensical phrase "you'll think they're the best thing since anything".

It is also slightly odd, because canned pudding is a more recent invention than ice-cream, meaning that the best thing since ice cream would automatically be better than canned pudding, unless you were speaking at a time when canned pudding hadn't yet been invented. Depending on what exactly your feelings are, you should be saying something like: "The best thing since canned pudding would also have been the best thing since ice cream if it had come out before canned pudding had been invented" or "The best thing since ice cream is, just to clarify, also better than canned pudding."

Other examples include "best thing since Voltaire" (1923) and "best thing since we went to the Yalu River in Korea" (1975).

Of all examples, my personal favourite is "the best thing since indoor plumbing", as written in 1988 by Peter S. Wenz. I like this example for two reasons. Firstly, its date, at a time when sliced bread was really taking over, makes us realise just how good indoor plumbing is to be able to compete alongside this great thing. And secondly, it reminds us how lucky we are not to have to go outside and face the elements whenever we want to take advantage of some plumbing: One of life's truly great things.

As briefly mentioned earlier, you're welcome to continue or expand on this research, either by using Ngram or other tools. The Massive Blog always welcomes contributions via the comment function or directly to the author on Twitter @herrbench.


 

Friday 6 September 2013

Equilibrium in the Champions League II

This post is the sequel to the previous post, hence the II in the title. So you should probably read that first, if you haven’t already done so

Anyway, the previous post ranked the Champions League qualifiers from 1 to 32 according to their UEFA club coefficients and used these rankings as a basis for analysing the balance of the groups and measuring each team’s luck in the draw.

There are two other obvious ways of measuring the strength of the teams:
- Using the UEFA club rankings;
- Using the club coefficient points.

Using the UEFA club rankings
The UEFA club rankings seem like a good idea, because they keep the numbers as nice manageable integers and they add some detail as the gaps between teams aren’t all the same, thereby taking into account that some teams are significantly lower-ranked than others. For example, the top 6 ranked teams in the Champions League are also ranked 1 to 6 overall, but Austria Wien, 31st in the Champions League, are ranked 114 overall. 

The problem with using this ranking system is that Real Sociedad, the team ranked 32nd and worst of all the Champions League qualifiers, don’t have a UEFA ranking at all, because they haven’t been in Europe in the last five years. As there are 450 teams with a UEFA ranking, this would make Sociedad joint 451st

Unfortunately, this massive leap to the 32nd team (all other 31 teams are in the top 114) skews the entire system. In the same way as, with a 1-32 ranking system, we had a total 528 points and 66 per balanced group, this system gives us 1,328 and 166 per balanced group. 

However, the group with Sociedad will automatically be far worse than average and most groups will be far better, with the only way to get a balanced group being to have Vienna (114) and three other teams with a total 52 between them, such as Bayern (2), PSG (19) and Dortmund (31). Even the third worst-ranked team, Plzen (74) cannot be put in a balanced group, with the most balanced scenario having a total 145, with Benfica (9), Juventus (20) and Leverkusen (42) completing Plzen’s group.

This is clearly unsatisfactory and, as such, I reject the use of the UEFA club rankings as a workable system for looking to achieve balance. They may be useful next year, if there is not such an anomaly, but, for 2013/14, they must be set aside.

What about using the club coefficient points?
Using the club coefficient points avoids the problem with Sociedad. Although they have zero points, this is only 16.575 fewer than Vienna, which does not represent such a dramatic and exaggerated drop as 114th to 451st in the ranking. In fact, this is not even the largest difference between two adjacently-ranked sides, as Arsenal have  17 fewer than Man U.

So this system seems to be workable. And it takes into account larger and smaller gaps between teams than the more simple ranking system. So it could be worth a look. 

Balance using the coefficients
Following an equivalent methodology to the one for the rankings, we have a total 2454.519 points, so balanced groups would each have 2454.519/8 = 306.815 points. 

It is unlikely that we will be able to get 8 groups with this exact score but we could consider them fairly balanced if we had no group with more than 306.815+(306.815/32) and none with less than 306.815-(306.815/32). 306.815/32 is 9.588 so this means groups between 297.227 and 316.403.

The choice of 32 is fairly arbitrary, basically being used because there are 32 teams. If anyone has a better suggestion for something more suitable, they are welcome to comment.

Anyway, let’s start out by looking at the 8 groups which were balanced with the ranking system. These have scores of:


Group
Total coefficient
Difference to balanced group
A
310.932
+4.117
B
316.865

+10.050
C
292.228

-14.587
D
295.280

-11.535
E
315.223

+8.408
F
301.727

-5.088
G
299.211

-7.604
H
323.053

+16.238

Based on what I’ve said above, this would make suggest that groups A, E, F and G are fairly balanced, whilst B, C, D and H are either too strong (B and H) or too weak (C and D).

By making two simple swaps:
  • CSKA (D, 77.776) with Donetsk (H, 94.951
  • PSG (C, 71.800) with Schalke (B, 84.922)
we redress this imbalance and come out with 8 balanced groups.

Of course, making these two changes brings about imbalance according to the 1-32 ranking system. However, if we fiddle about with the spreadsheet for long enough, then we can come up with the following groups:

Group A


Group B


Man U
130.592
5
Real
136.605
4
Schalke
84.922
12
Juventus
70.829
16
Basel
59.785
21
Zenit
70.766
17
Celtic
37.538
28
Bucharest
35.604
29
Totals
312.837
66
Totals
313.804
66
Group C


Group D


Benfica
102.833
8
Bayern
146.922
2
CSKA
77.766
14
Donetsk
94.951
10
Man City
70.592
18
Olympiakos
57.800
22
Napoli
46.829
26
Sociedad
0.000
32
 Totals
298.020
66
Totals
299.673
66
Group E


Group F


Chelsea
137.592
3
Arsenal
113.592
6
Marseilles
78.800
13
Atletico
99.605
9
Dortmund
61.922
20
Leverkusen
53.922
24
Plzen
28.745
30
Anderlecht
44.880
27
Totals
307.059
66
Totals
311.999
66
Group G


Group  H


Porto
104.833
7
Barcelona
157.605
1
Milan
93.829
11
PSG
71.800
15
Galatasaray
54.400
23
Ajax
64.945
19
Copenhagen
47.140
25
Vienna
16.575
31
Totals
300.202
66
Totals
310.925
66

Now it took quite a long time for me to get such a distribution which suggests that there aren’t all that many possible draws which offer balance according to both ways of measuring. This is not, however, by any means to say that this is the only way.

Whilst it is nice to see that it is possible, given the fact that 1/32nd deviation from the average was chosen rather unjustifiably, I could have chosen something less stringent and achieved balance with that more easily, if I’d wanted to.

And what about lady luck?
As we saw in the previous post, you can measure the luck of a team by comparing its actual draw, that is the strength of its actual opponents, with the strength its opponents would have in balanced groups. In the previous post, the luck (l) was calculated as:
l = (g-66)/3
where (g) was the total ranks of the group and 66 the rank of an average group.

The equivalent formula with the club coefficients, if we say k is now luck and the group total is h, would then be:
k = (h-306.815)/3

However, as we want good luck to be positive, we need to switch this around to take into account the fact that a high-numbered coefficient, unlike a high-numbered ranking, is given to a strong team. So we can make it:
k = (306.815-h)/3.

Luck (k) of the English
We saw in the previous post that, contrary to the claims of the BBC and, in particular, Phil McNulty, Arsenal and Chelsea were equally (and only slightly) unlucky, Man City had the worst luck and Man Utd were the only English side to get lucky.

If we measure luck (k) of the English teams, as formulated above, we get:
Man City with -5.74
Arsenal with +1.89
Chelsea with -3.70
Man Utd with +9.11

Clearly, whilst Man City and Man Utd retain their positions from the previous post as most unlucky and luckiest respectively, we see a significant change with Arsenal and Chelsea. 

Chelsea stay unlucky but Arsenal emerge as being a little bit on the lucky side of balanced. This is perhaps not a surprise as Arsenal’s, though ranked 6, are a long way behind the 5 top-ranked teams in terms of coefficient points. So measuring by coefficient points, they deserve, as it were, to get somewhat stronger opponents. 

Luck (k) of the Celtic
In the last post, Celtic were very unlucky. When measuring according to coefficient points, this doesn’t change much, as they come out with a luck (k) score of -15.70, making them 2.73 times more unlucky even than Man City, the unluckiest of the English sides. And, as with luck (l), Celtic (and the other teams in group H) have the most rotten luck (k) of all teams in the competition.

Arsenal, however, prove to be much more fortunate than a lot of pundits would have us believe.